Aksel or Kusayla (died in the year 690, Berber: Aksil or Aksel, Tifinagh script: ⴰⴽⵙⴻⵍ) was a 7th century leader of the Awraba tribe of the Berber people and head of the Sanhadja confederation. He is known for prosecuting effective Romano-Berber resistance against the Muslim Arab expansion into North Africa in the 680s.
His homeland was Tlemcen in modern Algeria, according to Ibn Khaldun. However, this account dates from the 14th century, some 700 years later; other sources closer to Kusaila's time (9th century are the earliest available) associate him only with the Awras area. Kusaila grew up during the time of the Byzantine exarchate in North Africa and was probably educated in Romano-Byzantine ways.
According to late accounts (11th century through to Ibn Khaldun in the 14th century) the amir of the invading Arabs, who was then a freed slave called Abu al-Muhajir Dinar, surprisingly invited Kusaila to meet with him in his camp. Abu al-Muhajir convinced him to accept Islam and join his army with a promise of full equality with the Arabs (678). Abu al-Muhajir was a master in diplomacy and thoroughly impressed Kusaila with not only his piety but with his high sense of respect and etiquette. Kusaila incorporated the Awraba-Sanhajda into the conquering Arab force and participated in their uniformly successful campaigns under Abu al-Muhajir. This amir was then forcibly replaced by Uqba ibn Nafi who treated Kusaila and his men with contempt. Eventually Uqba's disrespect enraged Kusayla and provoked a plot of revenge. On the army's return from Morocco, Uqba allowed his troops to break up and go home. The remainder, about 5,000, was vulnerable and exhausted. On the return march to Kairowan, Kusaila joined with the Byzantine forces and organised an ambush. The Christian-Berber force, about 50,000 strong, defeated the Arabs and felled Uqba at Tahudha near Biskra (683). Kusaila now held undisputed mastery over North Africa and marched to Kairowan in triumph.
The above account is disputed by some historians, who prefer the earlier 9th-century sources. According to these, Abu al-Muhajir had no connection with Kusaila, nor did Uqba ibn Nafi until he was ambushed at Tahudha. These earlier sources also describe Kusaila as a Christian, not a Muslim convert. They do agree, however, that he led a combined Byzantine-Berber force when he defeated Uqba.
In 688 Arab reinforcements arrived under Zuhair ibn Kays. Kusaila met them in 690 at the Battle of Mamma. Vastly outnumbered, the Awraba were defeated and Kusaila was killed. It was not the last instance of Berber resistance, however (see al-Kahina).